What is the initial value for the function f(x)=3(5/4)x

For

you seem to want to know the value of f(0). Put 0 where x is, then evaluate.


The initial value of the function is 3.

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You will observe that when x=0, the exponential term evaluates to 1. This is true regardless of its base. Thus f(0) is always the coefficient of the exponential term—in this case, 3.

If you meant for f(x)=3(5/4)x to represent an exponential function, please use " ^ " to indicate exponentiation:

f(x)=3(5/4)^x

The initial value is the value of f(x) when x = 0:  f(0) = 3(5/4)^0 = 3(1) = 3.